Device-based therapies in cardio-renal syndrome: a pathophysiology-driven approach to a complex bidirectional disease

Cardiorenal syndrome (CRS) is a complex clinical condition characterized by the simultaneous relationship between cardiac and renal dysfunction, often complicating the management of heart failure. Despite advancements in guideline-directed medical therapy, persistent congestion and diuretic resistance continue to be prevalent and are closely linked to negative outcomes. Device-based therapies have shown potential as adjunctive strategies to address critical pathophysiologic mechanisms of CRS not adequately addressed by pharmacologic approaches alone. This review offers a current perspective on device therapies for CRS, presented in accordance with their predominant mechanistic effects on volume regulation and hemodynamics. It is crucial to underscore the necessity of individualized patient selection, which is determined by the underlying hemodynamic phenotype, renal sodium avidity, diuretic responsiveness, and congestion burden, rather than isolated changes in renal function. We suggest a phenotype-driven stepwise management implementation algorithm to potentially aid appropriate timing and selection of device-based interventions. Also considered are practical considerations including procedural risk, integration into heart failure care pathways, and the role of device therapy in a broader disease-modifying strategy.